Naresh Patre
Ansys Employee

Mark McGowan 

There doesn't seem a direct way to project parts of stl that don't pass through the plane. below are a couple of options you can try out:

1. Create another plane passing through the other parts of the stl. Then use the process mentioned earlier to get the edges are splitting the stl part.

2. Convert the other stl parts to solid body. You can then use project tool to project the solid body on to a surface.